I'll be that guy and say that there's no point trying to make this concept work. don't try to make something work for the sake of making it work; you don't get good cards that way. try to make something work if it's cool in some way and just has problems. that said
Each other player reveals cards form his deck until he reveals a non-Victory card costing $3 or more and discards the rest. He may trash it. If he does, you may gain it. Otherwise, he gains a Copper.
This is not really an alternative of the original idea, it's more of a saboteur variant. And it's still political. Play 3P, reveal a silver. I'd rather just lose this silver than gaining a copper, but I don't want you to have it.
Is helping one of you worth helping myself? -> political.
Each player reveals the top card of his deck. You may gain it if it costs $4 or less.
this is a Rogue/Jester variant. it sounds okay, though worse than those two, because it's much swingier.
Each other player discards the top card of his deck. He may put it into his hand. If he does, you may gain a copy of it.
another Jester variant. if it hits
-> green cards/bad cards, it's useless vs Jesters junking
-> good non-Victory cards, it's weaker because you help your opponent
-> okay non-victory cards, it's slightly weaker